feat: add swift implementation to lcci problem: No.10.02 (#2712)

Author: klever34

Diff for: lcci/10.02.Group Anagrams/README.md

@@ -120,6 +120,19 @@ function groupAnagrams(strs: string[]): string[][] {
 }
 ```
 
+```swift
+class Solution {
+    func groupAnagrams(_ strs: [String]) -> [[String]] {
+        var d = [String: [String]]()
+        for s in strs {
+            let t = String(s.sorted())
+            d[t, default: []].append(s)
+        }
+        return Array(d.values)
+    }
+}
+```
+
 <!-- tabs:end -->
 
 ### 方法二：计数

Diff for: lcci/10.02.Group Anagrams/README_EN.md

@@ -127,6 +127,19 @@ function groupAnagrams(strs: string[]): string[][] {
 }
 ```
 
+```swift
+class Solution {
+    func groupAnagrams(_ strs: [String]) -> [[String]] {
+        var d = [String: [String]]()
+        for s in strs {
+            let t = String(s.sorted())
+            d[t, default: []].append(s)
+        }
+        return Array(d.values)
+    }
+}
+```
+
 <!-- tabs:end -->
 
 ### Solution 2: Counting

Diff for: lcci/10.02.Group Anagrams/Solution.swift

@@ -0,0 +1,10 @@
+class Solution {
+    func groupAnagrams(_ strs: [String]) -> [[String]] {
+        var d = [String: [String]]()
+        for s in strs {
+            let t = String(s.sorted())
+            d[t, default: []].append(s)
+        }
+        return Array(d.values)
+    }
+}